63 ballast resistor and coils

[Clem Z.]

i have used the .3 ohm resistor with every GM

coil ever made,chevy,olds,buick and pontiac and never saw any problems with the coil. we were just looking for a hotter spark back then. when we were serious we would move the wires on the resistor to bypass it just for those late night back road races.JMHO

[Michael H.]

July 63 Parts Book (resistor)

Here's the resistor that goes with a specific coil/engine combo. Hope this clears up this mess once and for all. I sure hope someone is recording all of the corrections for the 63-64 JG. Hate to think we were wasting all this time for nothing. Sorry if I sound irritated, but I am. No excuse for some of this incorrect info in the JG.

[John D.]

Re: i have used the .3 ohm resistor with every GM

Clem, Going past your house in a day or so to pick up catalogs-Alpha. We should do lunch.
Meanwhile I see I have opened up a big can of worms. Glad I did though and appreciate all the fine answers. I printed some of it-especially Michaels sheets and will put it in glove box. Now Clem find me a nice original 091. We used to run the 202's instead. Took a 202 out of the 63. Barry H told me one day I talk about using hot spark plugs too much on the fuel cars. Should stress using the correct hot coil more and then the plugs wouldn't be such an issue. Jumping the resistor block huh. Timmy used to put a piece of rubber behind the cheep Delco points so they wouldn't bounce. Remember that trick. My old 65 would go to 7 grand. Remember missing a shift on the way to Kings Inn-up the road from Grabiaks. Goodbye tranny. Coasted down 22 to a halt. New car. Tranny was trashed. Good old days. John

[Clem Z.]

i later used a "dwell extender" which "closed"

the points electronically before they close mechanically increasing the dwell time. i could use a double spring single point it would allow you to turn the engine to 7500+ RPMs

[Clem Z.]

do not the coil bracket cover the coil #s

on some coils since the numbers are on the bottom????

[John D.]

Re: do not the coil bracket cover the coil #s

Clem, It is up to the car owner to make sure the numbers are available for scrutiny otherwise they may get a hit on the judging floor. John

[Tracy C.]

Thanks Michael for taking the time to post pics! *NM*

[Clem Z.]

if the coil position in the bracket has to be

changed that is not "as delivered" to me

[John D.]

Re: if the coil position in the bracket has to be

Clem, As delivered to you in the olden days meant putting in three tail lights, taking off the emblems, taking off front bumper and other stuff in Floyd's body shop. Correct? Who would be caught dead in our area with a front bumper? Brand new car and took it home with no front bumper and still remember my Dad yelling. heee. That's as delivered. The coil can be as delivered but if the boys (and girls) can't read it you don't get a slash-you get dinged. By the way still like the chunk of rubber behind the points. Timmy did it and got a big kick out of it. Couldn't keep up with Danny's TI car though. It would out rev the cheep points. I couldn't rev high enough. Think you will beat Danny next time A new model Corvette comes out. I certainly hope so as boy does he brag. John

[Jack H.]

Re: 63 ballast resistor and coils

"As far as the "black dot" and "blue stripe" to identify the 0.3 and 1.4 ohm ballasts, respectively, I'm not convinced that so marked parts were used in production, but service replacements were apparently so marked."

That's been kicked around a lot (were the factory production ballast resistors color coded?)... All I can say is:

(1) In service, the ballast resistors were packaged in individual boxes giving a conveninent place for distinction (part no. short/long).

(2) At the factory, it's a good bet they weren't individually boxed and both versions could have been shelved/binned making color coding useful...

(3) If you pull the respective drawings (19578154 and 1931385), the requirement to color code the parts is called out and there doesn't appear to be a running change associated with color coding process.

[Ray C.]

Re: 63 ballast resistor and coils

After reading this discussion I am not sure what resistor/coil combination to use. What is the recommended choice for a 1963 340HP? The 63 is restored to original specifications including the engine, but I do love to drive it and I would like dependability. 087 coil with D1110 1.4 ohm resitor as per 1963-JG or 091 with D1111 0.3 ohm resitor which seems to be the consenious of the correct combination for 1963 high performance.

Thanks Ray

[Michael H.]

Re: 63 ballast resistor and coils

Ray,

The correct original coil/resistor for your 340 HP car is the 091 coil with the 1931385 black dot resistor. This is the combination that your car would have had when it left the plant.

If you now have the 087 coil and blue stripe resistor that was originally listed for late production 250-300 HP cars, it will function satisfactorily. If you have no intentions of having the car judged, there's really no absolute need to change to the 091/385 coil and resistor unless you want everything dead on correct and original.

Also, as Jack mentioned above, I believe these resistors were color coded when they arrived on the assy line and all originals would have had either the black dot or blue stripe.

[Ray C.]

Re: 63 ballast resistor and coils

Thanks Michael

I am currently using a Blue Streak coil with an aftermarket resistor that is rated at .9 Ohm and it is running fine. I would like to replace the coil with a correct Delco coil. I have an original or NOS 1931385 black dot resistor so I guess I will be looking for the 091 coil while at Carlisle.

Thanks Ray

[Jack H.]

Re: 63 ballast resistor and coils

OK, the typical progression was to use the 'hot' coil ('091) with the 'hot' ballast (0.3 ohm, '385 or D1111) which was the factory combo for all early '63 Corvettes. Plus, this setup was used for YEARS on straight axle cars back to '58...

The change was made on 2/4/63 to install a 'cold' coil ('087) with the 'cold' ballast (1.8 ohm, '154 or D1110) on the low reving, hydraulic lifter engines and keep the 'hot' setup on the high reving, solid lifter engines.

But, I believe it was John Hinckley, who pointed out the change happened in two separate paperwork releases (the ballast and then the coil) making it look like the change was an across-the-board transistion to all cars built in late '63 (cold ignition setup). Currently, here's the way the NCRS JG books read:

(1) All early '63 cars have 'hot' ignition setup.

(2) All late '63 cars have 'cold' ignition setup.

(3) All low rev/hyd lifter engines have 'cold' ignition setup in '64 and all high rev/solid lifter engines have 'hot' ignition setup in '64.

Best info says the '63 JG is wrong and late '63 engines were actually configured as they were in '64 with the difference being both the coil and the ballast based on the engine's ability to rev.

Now, to complicate things, there was a Technical Service Bulletin (DR #577) that came out in late Feb, 1963. It informed dealer service folks about the ignition change and also told them they could CHANGE the 'hot' ballast to a cold 'ballast' if they had customers complaining of reduced point life... Note that's NOT telling them to change the coil along with the ballast!

Also, the TSB says this affects similarly configured 'hot' ignition setups in other Chevy cars (Turbo charged Corvair, Chevy 409) but that this change (swap just the ballast) should only be made for TEMPORARY SEASONAL OPERATION (winter use). So, you should now be REALLY confused as a lot of us are!!!!

[Ray C.]

Re: 63 ballast resistor and coils

Thanks! Jack

Now that my mind is totally spinning with information, I have one simple question. If you were running a 340HP 63, what combination would you use?

Ray